I picked up a Haida ND8 filter from Photosphere recently. I've been wanting to buy an ND8 for the longest time, since I have the ND106 and ND110 (6 and 10 stops respectively) from B+W. These are useful at different times of the day to smoothen out water, introduce cloud motion, remove people through motion blur, etc, depending on what your needs are. As a clarification, I have never used other brands' ND8 so this is really just a sharing of thoughts of how the Haida ND8 matches up to my expectations. Note: ND106 and ND110 are stronger ND filters and the B+W versions introduce a warm cast to your photograph. I'm told that the Haida versions introduce a slightly cool cast, so the approach is probably closer to the Lee Big Stopper (which costs a bomb more).
For myself, I have tried GND filters stacked with ND filters throughout the years and ended up just using ND. Why? Unless you get mega-expensive Lee filters, the next level down, which is Hi-tech will give you color casts when stacking. And if you mix Lee with Hi-tech, you get color casts! To add to that, many scenes such as cityscapes do not work well with GND, owing to the fact that you would also darken the buildings which are in the section with the sky which the GND selectively darkens. So frankly, in my opinion, a set of good ND filters and a sturdy tripod is all one really needs, along with good know-how in Photoshop to manually blend your photographs. An alternative is HDR. Some may ask: "But what happens if you have a glorious sunset with moments to spare?" Then capture the sky first! Then handle the other details later on. It will merge fine.
That aside, let's cut to the chase. In the first post I'll just talk about the less important factors (for me), and in the second post some pictures taken with the filter.
Just to get it out of the way, since some people find it a niggling point. I myself don't really care as long as the box doesn't fall apart after 3 uses. It won't be a pleasant experience carrying around the naked filter in your bag, hard to find and dig out and all that. The Haida packaging imitates (can't think of a better word) the B+W packaging pretty well. I can't see or feel a difference other than the "Haida" wording there. It also comes in a paper box (which I'll be throwing away after doing this review).
B+W ND110 in packaging on the far left, Haida ND8 in packaging in centre, Haida outer paper box packaging on right
The Haida box came labelled "slim". It is indeed much slimmer than the B+W filters. I'll let the picture speak for itself. What this means for photographers, though, is if you're looking into stacking ND and GND, the B+W options matched with the cheaper Cokin P series sized Hi-tech filters yield minor amounts of vignetting. This is correctable of course. If you stack the Haida and P series GNDs (note: using the ultra wide angle filter ring of course), I wager that you won't see any vignetting whatsoever.
I found the Hoya ND400 when I had it to be a pain in the arse to clean. Yes, it could be cleaned but for some reason the multicoating always ended up looking smeared whenever I used lens cleaning solution to remove stubborn oil stains. The Haida ND8 is purportedly multicoated too, and you do see a bit of that, but it cleans off with one or two extra wipes (compared to the "polishing" you would have to do with the Hoya). I'd give this top marks for cleanability.